<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
    <style>
        #d1{
            width: 100px;
            height: 100px;
            border: 1px solid red;
            /*margin-top: 50px;
            margin-left: 30px;
            margin-bottom: 100px;
            margin-right: 20px;*/
            /*四个方向*/
            /*margin: 50px;*/
            /*上下20  左右40*/
            /*margin: 20px 40px;*/
            /*上右下左 顺时针*/
            /*margin: 10px 20px 30px 40px;*/
            margin-bottom: 100px;
        }
        #d2{
            width: 100px;
            height: 100px;
            border: 1px solid red;
            /*上下相邻彼此添加外边距 取最大值*/
           margin-top: 150px;
        }
        #s1{
            /*行内元素上下外边距无效*/
            margin-bottom: 100px;
            margin-right: 100px;
        }
        #s2{
            margin-left: 50px;/*左右相邻彼此添加外边距两者相加*/
        }
    </style>
</head>
<body>
<span id="s1">span1</span><span id="s2">span2</span>
<div id="d1"></div>
<div id="d2"></div>
</body>
</html>